Mixer tank cover assembly

Abstract

A food ingredient mixer includes a tank defining an internal mixing volume, the tank including an upper opening, and an agitator disposed in the internal mixing volume and movable for mixing ingredients and a cover assembly associated with the upper opening, the cover assembly including a first part through which ingredients may be added to the internal mixing volume and a second part movable between a first position that overlies the first part and a second part that exposes the first part.

What is claimed is: 
     
         1 . A food ingredient mixer, comprising:
 a tank defining an internal mixing volume, the tank including an upper opening;   an agitator disposed in the internal mixing volume and movable for mixing ingredients;   a cover assembly associated with the upper opening, the cover assembly including:
 a screen member movable between a closed position covering the upper opening and an open position uncovering the upper opening, the screen member including a plurality of openings through which ingredients can be added to the tank when the screen member is in the closed position; and 
 a lid member movable between a closed position covering the upper opening and an open position uncovering the upper opening, wherein the lid member overlies the screen member when the lid member is in the closed position, wherein, in a first configuration of the cover assembly, the lid member is movable from its closed position to its open position while the screen member remains in its closed position, wherein, in a second configuration of the cover assembly, the lid member and the screen member are movable together between their respective closed positions and open positions; and 
   at least one releasable latch member between the screen member and the lid member for selectively placing the cover assembly in the first configuration or the second configuration.   
     
     
         2 . The mixer of  claim 1 , further comprising at least one latch system for holding the lid member and the screen member in respective fully open positions during cleaning of the internal mixing volume. 
     
     
         3 . The mixer of  claim 1 , further comprising:
 an agitator drive for controlling movement of the agitator; and   a control system configured for controlling the agitator drive based at least in part upon the position of at least one of the lid member or the screen member.   
     
     
         4 . The mixer of  claim 3 , wherein the control system is configured to detect movement of the screen member out of its closed position and, in such case, to prevent operation of the agitator drive. 
     
     
         5 . The mixer of  claim 4 , wherein the control system is configured to detect movement of the lid member out of its closed position, while the screen member remains in its closed position, and, in such case to reduce a speed of the agitator drive from a set operating speed to an ingredient add speed. 
     
     
         6 . The mixer of  claim 5 , wherein the control system is configured to increase the speed of the agitator drive from the ingredient add speed to the set operating speed based at least in part upon detection of the lid member being moved back to its closed position. 
     
     
         7 . The mixer of  claim 6 , wherein the control system is configured such that a predefined time condition must also be met before the control system increases the speed of the agitator drive from the ingredient add speed to the set operating speed. 
     
     
         8 . The mixer of  claim 1 , further comprising a pivot shaft, wherein the lid member is pivotably connected for pivot about the pivot shaft and the screen member is pivotably connected for pivot about the pivot shaft. 
     
     
         9 . The mixer of  claim 8 , wherein the pivot shaft is external of the internal mixing volume, and the lid member includes at least one opening through which the screen member is pivotably connected to the pivot shaft. 
     
     
         10 . The mixer of  claim 9 , further comprising at least one latch system for holding the lid member and the screen member in their respective closed conditions. 
     
     
         11 . The mixer of  claim 1 , wherein a pair of pneumatic cylinders are connected to control movement of the lid member and, when the cover assembly is in the second configuration, the screen member with the lid member. 
     
     
         12 . A food ingredient mixer, comprising:
 a tank defining an internal mixing volume, the tank including an upper opening;   an agitator disposed in the internal mixing volume and movable for mixing ingredients; and   a cover assembly associated with the upper opening, the cover assembly including a first part through which ingredients may be added to the internal mixing volume and a second part movable between a first position that overlies the first part and a second part that exposes the first part, wherein the first part comprises a pivotable screen member and the second part comprises a pivotable lid member.   
     
     
         13 . A food ingredient mixer, comprising:
 a tank defining an internal mixing volume, the tank including an upper opening;   an agitator disposed in the internal mixing volume and movable for mixing ingredients;   a cover assembly associated with the upper opening, the cover assembly including:
 a screen member movable between a closed position covering the upper opening and an open position uncovering the upper opening, the screen member including a plurality of openings through which ingredients can be added to the tank when the screen member is in the closed position; and 
 a lid member movable between a closed position covering the upper opening and an open position uncovering the upper opening, wherein the lid member overlies the screen member when the lid member is in the closed position, wherein, in a first configuration of the cover assembly, the lid member is movable from its closed position to its open position while the screen member remains in its closed position; 
   an agitator drive for controlling movement of the agitator; and   a control system configured for controlling the agitator drive based at least in part upon the position of at least one of the lid member or the screen member, wherein the control system is configured to detect movement of the screen member out of its closed position and, in such case, to prevent operation of the agitator drive.   
     
     
         14 . The mixer of  claim 13 , wherein the control system is configured to detect movement of the lid member out of its closed position, while the screen member remains in its closed position, and, in such case to reduce a speed of the agitator drive from a set operating speed to an ingredient add speed. 
     
     
         15 . The mixer of  claim 14 , wherein the control system is configured to increase the speed of the agitator drive from the ingredient add speed to the set operating speed based at least in part upon detection of the lid member being moved back to its closed position. 
     
     
         16 . The mixer of  claim 15 , wherein the control system is configured such that a predefined time condition must also be met before the control system increases the speed of the agitator drive from the ingredient add speed to the set operating speed.